Agreement and Accuracy of Different Devices for Biometry Measurements in Patients With Cataract

Not Applicable

Brief Summary: The rationale of this study is to compare repeatability, reproducibility and agreement of three different AS-OCT devices and Pentacam.

The investigational devices are approved biometry and keratometry devices to perform biometric/keratometric measurements preoperatively before cataract surgery. The measurements are used to calculate the needed IOL power.

Measurements with all four devices will be performed 3 times consecutively by two trained observer. The order of the observer, the order of devices as well as the eye (left/right) is randomized.

Examinations will be implemented in accordance with the approved investigational plan on subjects and includes: repeated biometry/keratometry with four different devices

Detailed Description: The rationale of this study is to compare repeatability, reproducibility and agreement of both, AS-OCT(s) and Pentacam. In our department three different AS-OCT devices and a HR Scheimpflug imaging device are currently in use for clinical routine to measure the cornea. Among refractive and anterior segment surgeons, there is no preferred and accepted method for accurate measurements of the corneal curvature. The four diagnostic tools are based on different technical and physical imaging principles and to date only limited information on their comparability exist. One advantage of ASOCT represents faster imaging speed when compared to Scheimpflug imaging. Thus, imaging misalignment, segmentation errors and defocus aberration can most likely be avoided by AS-OCT. Chen et al demonstrated that HR Scheimpflug imaging measurements of CCT were systematically higher than the measurements provided by FD AS-OCT. Further, repeatability, reproducibility and agreement of AS-OCT and Scheimpflug imaging device will be assessed during follow-up.

Recruitment & Eligibility

Inclusion Criteria

Age-related cataract
Age 40 and older (females of childbearing age will be interviewed if pregnancy is possible)

Exclusion Criteria

Contact lens wear within 5 days
Pathologic changes of the cornea, eye lid or conjunctiva on slit- lamp examination
History of corneal ocular surgery
Microphthalmus
Recurrent intraocular inflammation of unknown etiology
Blind fellow eye
Uncontrolled systemic or ocular disease

Arm && Interventions

Group	Intervention	Description
Casia II®	Keratometry	Keratometry will be performed three times consecutively.
IOL Master® 700	Biometry	Biometry will be performed three times consecutively.
Pentacam®	Keratometry	Keratometry will be performed three times consecutively.
IOL Master® 700	Keratometry	Biometry will be performed three times consecutively.
Spectralis Anterion®	Biometry	Biometry will be performed three times consecutively.
Spectralis Anterion®	Keratometry	Biometry will be performed three times consecutively.

Primary Outcome Measures

Name	Time	Method
Agreement of the four devices measuring mean keratometry value.	1 year	The measured K-Value of each device and the k-values within one device will be compared

Secondary Outcome Measures

Name	Time	Method
Agreement of the four devices measuring mean steep keratometry value.	1 year	The measured steep K-Value of each device and the steep k-values within one device will be compared
Agreement of the four devices measuring mean flat keratometry value.	1 year	The measured flat K-Value of each device and the flat k-values within one device will be compared
Agreement of the four devices measuring mean true keratometry value.	1 year	The measured true K-Value of each device and the true k-values within one device will be compared
Agreement of the devices measuring mean axial length	1 year	The measured axial length of each device and the axial length within one device will be compared
Agreement of the devices measuring mean lens thickness	1 year	The measured lens thickness of each device and the measured lens thickness within one device will be compared
Agreement of the devices measuring mean white-to-white measurement	1 year	The measured white-to-white distance of each device and the measured white-to-white distance within one device will be compared

Locations (1): Medical University of Vienna Allgemeines Krankenhaus
🇦🇹
Vienna, Austria